When \( 100 \mathrm{~mL} \) of \( 1.0 \mathrm{M} \mathrm{HCl} \) was mixed with \( 100 \mathrm{~mL} \) of \( 1.0 \mathrm{M} \mathrm{NaOH} \) in an insulated beaker at constant pressure, a temperature increase of \( 5.7^{\circ} \mathrm{C} \) was measured for the beaker and its contents. (Expt-1). Because the enthalpy of neutralisation of a strong acid with a strong base is a constant \( \left(-57.0 \mathrm{kJmol}^{-1}\right) \), this experiment could be used to measure the calorimeter constant. In a second experiment (Expt-2), \( 100 \mathrm{~mL} \) of \( 2.0 \mathrm{M} \) acetic acid \( \left(K_{a}=20 \times 10^{-5}\right) \) was mixed with \( 100 \mathrm{~mL} \) of \( 1.0 \mathrm{M} \mathrm{NaOH} \) (under identical conditions to (Expt-1)) where a temperature rise of \( 5.6^{\circ} \mathrm{C} \) was measured. (Consider heat capacity of all solutions as \( 4.2 \mathrm{Jg}^{-1} \mathrm{~K}^{-1} \) and density of all solutions as \( 1.0 \) \( \left.\mathrm{g} \mathrm{mL}^{-1}\right) \)
Enthalpy of dissociation (in \( \mathrm{kJ} \mathrm{mol}^{-1} \) ) of acetic acid obtained from the Expt-2 is :
(A) \( 1.0 \)
(B) \( 10.0 \)
(C) \( 24.5 \)
(D) \( 51.4 \)
ЁЯУ▓PW App Link - https://bit.ly/YTAI_PWAP
ЁЯМРPW Website - https://www.pw.live
0